sabre

Stuff like accounts payable is ignored as it is part of working capital, smth which relates to mainstrem revenue-generating activities, rather than financing.
I guess minority interest (NCI) is added to account for the cost of 100% acquisition of all the subs down the group structure. Or to ensure consistency of ratios as Aether mentioned.
Without subs’ financial statements you cannot calculate the parent’s share of Revenues or EBITDA in the subs. The only items disclosed are P/L attributable to owners of the parent and non-controlling interest. As such EV/EBITDA or EV/Sales can be calculated only for the group as a whole (before deducting NCI from the P/L and after adding NCI to equity and debt)
I believe the last idea is the basic reasoning behind adding NCI.